DOCSLIB.ORG

Seabed Mapping: a Brief History from Meaningful Words

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Seabed Mapping: a Brief History from Meaningful Words geosciences Review Seabed Mapping: A Brief History from Meaningful Words Pedro Smith Menandro and Alex Cardoso Bastos * Marine Geosciences Lab (Labogeo), Departmento Oceanografia, Universidade Federal do Espírito Santo, Vitória-ES 29075-910, Brazil; [email protected] * Correspondence: [email protected] Received: 19 May 2020; Accepted: 7 July 2020; Published: 16 July 2020 Abstract: Over the last few centuries, mapping the ocean seabed has been a major challenge for marine geoscientists. Knowledge of seabed bathymetry and morphology has significantly impacted our understanding of our planet dynamics. The history and scientific trends of seabed mapping can be assessed by data mining prior studies. Here, we have mined the scientific literature using the keyword “seabed mapping” to investigate and provide the evolution of mapping methods and emphasize the main trends and challenges over the last 90 years. An increase in related scientific production was observed in the beginning of the 1970s, together with an increased interest in new mapping technologies. The last two decades have revealed major shift in ocean mapping. Besides the range of applications for seabed mapping, terms like habitat mapping and concepts of seabed classification and backscatter began to appear. This follows the trend of investments in research, science, and technology but is mainly related to national and international demands regarding defining that country’s exclusive economic zone, the interest in marine mineral and renewable energy resources, the need for spatial planning, and the scientific challenge of understanding climate variability. The future of seabed mapping brings high expectations, considering that this is one of the main research and development themes for the United Nations Decade of the Oceans. We may expect a new higher resolution ocean seafloor map that might be as influential as The Floor of the Oceans map. Keywords: seabed mapping; seafloor mapping evolution; lexical analysis 1. Introduction Although the first documentation of studies concerning the sea date back to Aristotle’s time—384–322 AD, the beginning of marine sciences is generally considered to be the 17th century with Boyle’s “The Saltness of the Sea” (1674). One of the first bathymetric maps, if not the first, long before geophysical methods, was based on plumb measurements (fathoms units) and was published in an 1855 textbook by Matthew Fontaine Maury [1], who is considered to the father of modern oceanography. The HMS Challenger expedition (1873–1876) can be considered a striking fact of the seabed mapping history; much of the information preceding the 20th century presented herein were recovered from the “Report of The Voyage of HMS Challenger” [2]. More than 500 plumb measurements were acquired in the Challenger Expedition, revealing the depth of the Mariana Trench and the Dolphin, Connecting, and Challenge Ridges, known today as the Mid-Atlantic Ridge. At the beginning of the 20th century, an important theory regarding the ocean basins was put forth: the Wegener’s hypothesis of continental drift and seafloor spreading. In 1977, another milestone of seafloor mapping elaborated by Bruce Heezen and Marie Tharp [3] helped to consolidate the Wegener hypothesis and also illustrated submarine morphology in a reliable and similar way to what we know today [4,5]. Geosciences 2020, 10, 273; doi:10.3390/geosciences10070273 www.mdpi.com/journal/geosciences Geosciences 2020, 10, 273 2 of 17 Prior to the 19th century, the methods for depth measurements were archaic. The “lead and line” system is a classical example, in which a plumb attached to a cable sank through the water column until it reached the seafloor. Such measurements were greatly influenced by vessel drift and marine currents. There had been a few attempts to improve the method, e.g., by Hooke during the 18th century and Brooke in the 19th century. In parallel, the lack of knowledge about the seafloor allowed hypotheses to emerge that were sometimes eccentric, such as a perpetual ice cover over the seabed (French naturalist Péron, 1805—mentioned in Thompson and Murray, 1885, Report on the Scientific Results of the Voyage of H.M.S. “Challenger” [2] p. 37). The operation to lay down the first telegraph cable across the Atlantic was an event of great importance, around 1850. This spawned and drove a need to produce better knowledge about the ocean depths and encouraged technological advances. By 1920, the development of acoustic technology changed the course of seabed mapping, and then “lead and line” measurements were gradually replaced by echo sounders. The German Meteor Expedition (1925–1927) surveyed the South Atlantic Ocean using echo sounding equipment and other oceanographic tools. During this expedition, among other findings, the continuity of the Mid-Atlantic Ridge was observed, now known as being by far the largest geological formation on Earth. Seismic methods also came into use during this period, with the first records in water-covered areas in 1926 (historical events can be found in [6]), and the first important marine survey with this technique conducted in 1938 [7]. Between the decades of 1950 and 1960, substantial progress and development was made on electronic stabilization, interferometric modulation and positioning improvement [8]. In the 1970s, new perspectives for seabed acoustic mapping were driven by a revolutionary multibeam bathymetry system [9]. In 1977, during the Jean Charcot Expedition, the first non-military versions of multibeam systems were employed—Seabeam and Hydrochart, for deep and shallow waters, respectively. These systems have greatly enriched the future of the seabed mapping and the quality of bathymetric surveys [10,11], already enabling the inference of seafloor characteristics from backscatter data [12]. After these enhancements to acoustic systems, the science related to seabed classification leveraged major developments and innovations, e.g., geomorphological and habitat classification using geophysical data such as bathymetry and side scan sonar. In recent years, the use of correlations between acoustic properties and biological and/or geological parameters has been successful, but this type of transformation of acoustic properties into physical properties has been used in submarine acoustics for substantially longer [13]. Over time, seabed mapping gained further importance due to technological developments, providing substantive contributions to a better understanding of tectonics and ocean spreading. In addition to the unquestionable scientific importance and essential relationship with other oceanographic fields, the role of seabed mapping has been paramount for national and international limit jurisdiction issues, first established in 1982 (Law of the Sea). This subject is closely related to fields such as economic zoning, natural resources management and the exploration of marine mineral and oil and gas resources. The main points and implications of Article 76 of the United Nations Convention on the Law of the Sea were reviewed [14,15], identifying, among other issues, the importance of geophysical methods. Even today, one often hears or reads—with a degree of frustration or regret—that we know more about the moon’s surface and even some other planets than about our own oceans, and that around 82% of the ocean floor is as yet unmapped [16]. A notorious example is the southeastern Indian Ocean mapping that was conducted to search for a Malaysian Airlines flight that disappeared. As a byproduct, that dataset revealed interesting geomorphological findings that improved the understanding of that ocean floor region [17]. As well as the “The Nippon Foundation—GEBCO Seabed 2030 Project” efforts to map the oceans’ floor by 2030, the importance of seabed mapping for several fields is also corroborated by the United Nations with the declaration of the Decade of Ocean Science for Sustainable Development (2021–2030), including the map of the oceans as one of the research and development priorities. Here, the goal is not to be an audacious and challenging historical review of marine sciences [18,19], nor an ocean mapping review [20,21], as it would demand a large historiographical effort and a study Geosciences 2020, 10, 273 3 of 17 of the cartography aspects. The purpose here is to provide a consistent picture of seabed mapping supported by scientific studies, visualize the evolution of mapping methods (from the 1930s until now), Geosciences 2020, 10, x FOR PEER REVIEW 3 of 17 and emphasize the main trends and challenges. In this context, the analyses performed were based onuntil a set now) of scientific, and emphasize manuscripts the main (dated trends between and challenges. 1930 and 2019) In this retrieved context, fromthe analyses the Brazilian performed virtual librarywere “Portal based on de Peria setó dicosof scientific da CAPES”. manuscripts The web (dated search between was conducted 1930 and using2019) theretrieved keyword from “seabed the mapping”.Brazilian Thevirtual assessments library “Portal comprised de Periódicos primarily da CAPES a vocabulary.” The web analysis, search presenting was conducted statistical using results the accordingkeyword to “seabed the main mapping and frequent.” The assessments words from comprised sets of manuscripts primarilyfrom a vocabulary each decade. analysis, The presenting logic was to implementstatistical an results important according outcome to the from main “machine and frequent learning” words and from “data sets science”, of manuscripts in which anfrom
Load more

Recommended publications
  • Deep-Sea Mining: the Basics
    A fact sheet from June 2018 NOAA Office of Ocean Exploration and Research Deep-sea Mining: The Basics Overview The deepest parts of the world’s ocean feature ecosystems found nowhere else on Earth. They provide habitat for multitudes of species, many yet to be named. These vast, lightless regions also possess deposits of valuable minerals in rich concentrations. Deep-sea extraction technologies may soon develop to the point where exploration of seabed minerals can give way to active exploitation. The International Seabed Authority (ISA) is charged with formulating and enforcing rules for all seabed mining that takes place in waters beyond national jurisdictions. These rules are now under development. Environmental regulations, liability and financial rules, and oversight and enforcement protocols all must be written and approved within three to five years. Figure 1 Types of Deep-sea Mining Production support vessel Return pipe Riser pipe Cobalt Seafloor massive Polymetallic crusts sulfides nodules Subsurface plumes 800-2,500 from return water meters deep Deposition 1,000-4,000 meters deep 4,000-6,500 meters deep Cobalt-rich Localized plumes Seabed pump Ferromanganeseferromanganese from cutting crusts Seafloor production tool Nodule deposit Massive sulfide deposit Sediment Source: New Zealand Environment Guide © 2018 The Pew Charitable Trusts 2 The legal foundations • The United Nations Convention on the Law of the Sea (UNCLOS). Also known as the Law of the Sea Treaty, UNCLOS is the constitutional document governing mineral exploitation on the roughly 60 percent of the world seabed that lies beyond national jurisdictions. UNCLOS took effect in 1994 upon passage of key enabling amendments designed to spur commercial mining.
    [Show full text]
  • Marie Tharp: Mapping the Seafloor of Back-Arc Basins, Mid-Ocean Ridges, Continental Margins & Plate Boundaries Vienna (Austria), EGU 2020-3676, 7/5/2020
    A Tribute to Marie Tharp: Mapping the seafloor of back-arc basins, mid-ocean ridges, continental margins & plate boundaries Vienna (Austria), EGU 2020-3676, 7/5/2020 Eulàlia Gràcia, Sara Martínez Loriente, Susana Diez, Laura Gómez de la Peña*, Cristina S. Serra, Rafael Bartolome, Valentí Sallarès, Claudio Lo Iacono, Hector Perea**, Roger Urgeles, Ingo Grevemeyer* and Cesar R. Ranero B-CSI at Institut de Ciències del Mar – CSIC, Barcelona *GEOMAR, Kiel, Germany **Universidad Complutense de Madrid, Facultad de Geologia, Madrid 1 The first steps of Marie Tharp • Marie Tharp, July 30, 1920 (Ypsilanti, Michigan) – August 23, 2006 (Nyack, New York) was an American geologist & oceano- graphic cartographer who, in partnership with Bruce Heezen, created the first scientific map of the Atlantic Ocean floor. • Tharp's work revealed the detailed topography and multi-dimensional geographical landscape of the ocean bottom. • Her work revealed the presence of a continuous rift-valley along the axis Fig. 1. A young Marie in the field helping his father, William E. of the Mid- Atlantic Ridge, causing a Tharp, a soil surveyor for United States Dpt. of Agriculture. Marie often paradigm shift in Earth Sciences that helped him with this task, which gave her an introduction to map- led to acceptance of Plate Tectonics making. From book “Soundings” by Hali Felt (2012). and Continental Drift. 2 Working at Columbia University Lamont Geological Observatory (NY) Fig. 2. Marie Fig. 3. at streets of Bruce New York, Heezen after she looking at a was hired to fathogram work by Dr. being Maurice produced by Ewing’, at an early the newly- echosounder formed (year 1940).
    [Show full text]
  • The Voyage of the “Challenger”
    The Voyage of the "Challenger" From 1872 to 1876 a doughty little ship sailed the seven seas and gathered an unprecedented amount of information about them, thereby founding the science of oceanography by Herbert S. Bailey, Jr. UST 77 years ago this month a spar­ since that pioneering voyage. It was the philosophy at the University of Edin­ decked little ship of 2,300 tons Challenger, rigged with crude but in­ burgh. He did some dredging in the sailed into the harbor of Spithead, genious sounding equipment, that Aegean Sea, studying the distribution JEngland. She was home from a voyage charted what is still our basic map of of flora and fauna and their relation to of three and a half years and 68,890 the world under the oceans. depths, temperatures and other factors. miles over the seven seas. Her expedition Before the Challenger, only a few iso­ Forbes never dredged deeper than about had been a bold attack upon the un­ lated soundings had been taken in the 1,200 feet, and he acquired some curious known in the tradition of the great sea deep seas. Magellan is believed to have notions, including a belief that nothing explorations of the 15th and 16th cen­ made the Rrst. During his voyage around lived in the sea below 1,500 feet. But turies. The unknown she had explored the globe in 1521 he lowered hand lines his pioneering work led the way for the was the sea bottom. When she had left to a depth of perhaps 200 fathoms Challenger expedition.
    [Show full text]
  • Marie Tharp, Oceanographic Cartographer, Dies at 86 - New York
    Marie Tharp, Oceanographic Cartographer, Dies at 86 - New York... http://www.nytimes.com/2006/08/26/obituaries/26tharp.html?_r=0... August 26, 2006 By MARGALIT FOX Marie Tharp, an oceanographic cartographer whose work in the 1950’s, 60’s and 70’s helped throw into relief — literally — the largely uncharted landscape of the world’s ocean floor, died on Wednesday in Nyack, N.Y. She was 86 and a resident of South Nyack. The cause was cancer, according to the Lamont-Doherty Earth Observatory of Columbia University, which announced the death. Ms. Tharp was a researcher at the observatory from 1948 until her retirement in 1982. With her colleague Bruce C. Heezen (pronounced HAY-zen), Ms. Tharp compiled the first comprehensive map of the entire ocean bottom, illuminating a hidden world of rifts and valleys, volcanic ranges stretching for thousands of miles and mountain peaks taller than Everest. The map was published by the Office of Naval Research in 1977. In the revised edition of his book “The Mapmakers” (Knopf, 2000), John Noble Wilford, a science reporter for The New York Times, described their achievement this way: “Like other pioneering maps, the one by Heezen and Tharp is not complete and not always completely accurate. It is, nonetheless, one of the most remarkable achievements in modern cartography. It is the graphic summary of more than a century of oceanographic effort.” Ms. Tharp’s work in plotting the ocean’s bottom would also help gain acceptance for the theory of continental drift, still a fairly subversive proposition when she and Mr.
    [Show full text]
  • Cosmos: a Spacetime Odyssey (2014) Episode Scripts Based On
    Cosmos: A SpaceTime Odyssey (2014) Episode Scripts Based on Cosmos: A Personal Voyage by Carl Sagan, Ann Druyan & Steven Soter Directed by Brannon Braga, Bill Pope & Ann Druyan Presented by Neil deGrasse Tyson Composer(s) Alan Silvestri Country of origin United States Original language(s) English No. of episodes 13 (List of episodes) 1 - Standing Up in the Milky Way 2 - Some of the Things That Molecules Do 3 - When Knowledge Conquered Fear 4 - A Sky Full of Ghosts 5 - Hiding In The Light 6 - Deeper, Deeper, Deeper Still 7 - The Clean Room 8 - Sisters of the Sun 9 - The Lost Worlds of Planet Earth 10 - The Electric Boy 11 - The Immortals 12 - The World Set Free 13 - Unafraid Of The Dark 1 - Standing Up in the Milky Way The cosmos is all there is, or ever was, or ever will be. Come with me. A generation ago, the astronomer Carl Sagan stood here and launched hundreds of millions of us on a great adventure: the exploration of the universe revealed by science. It's time to get going again. We're about to begin a journey that will take us from the infinitesimal to the infinite, from the dawn of time to the distant future. We'll explore galaxies and suns and worlds, surf the gravity waves of space-time, encounter beings that live in fire and ice, explore the planets of stars that never die, discover atoms as massive as suns and universes smaller than atoms. Cosmos is also a story about us. It's the saga of how wandering bands of hunters and gatherers found their way to the stars, one adventure with many heroes.
    [Show full text]
  • Intern Report
    Insights from abyssal lebensspuren Jennifer Durden, University of Southampton, UK Mentors: Ken Smith, Jr., Christine Huffard, Katherine Dunlop Summer 2014 Keywords: lebensspuren, traces, abyss, megafauna, deposit-feeding, benthos, sediment ABSTRACT The seasonal input of food to the abyss impacts the benthic community, and changes to that temporal cycle, through changes to the climate and surface ocean conditions impact the benthic assemblage. Most of the benthic fauna are deposit feeders, and many leave traces (‘lebensspuren’) of their activity in the sediment. These traces provide an avenue for examining the temporal variations in the activity of these animals, with insights into the usage of food inputs to the system. Traces of a variety of functions were identified in photographs captured in 2011 and 2012 from Station M, a soft-sedimented abyssal site in the northeast Pacific. Lebensspuren creation, holothurian tracking, and lebensspuren duration were estimated from hourly time-lapse images, while trace densities, diversity and seabed coverage were assessed from photographs captured with a seabed- transiting vehicle. The creation rates and duration of traces on the seabed appeared to vary over time, and may have been related to food supply, as may tracking rates of holothurians. The density, diversity and seabed coverage by lebensspuren of different types varied with food supply, with different lag times for POC flux and salp coverage. These are interpreted to be due to selectivity of 1 deposit feeders, and different response times between trace creators. These variations shed light on the usage of food inputs to the abyss. INTRODUCTION Deep-sea benthic communities rely on a seasonal food supply of detritus from the surface ocean (Billett et al., 1983, Rice et al., 1986).
    [Show full text]
  • Marie Tharp: Seafloor Mapping and Ocean Plate Tectonics
    Marie Tharp: Seafloor mapping and ocean plate tectonics The pioneering seafloor mapping and visualization by Marie Tharp played a key role in the acceptance of the plate tectonic theory. Her physiographic maps, published with Bruce Heezen, covered the Earth’s oceans and revealed with astonishing accuracy the submarine landscape. Marie Tharp co-authored the first papers describing the major fracture zones in the Central Atlantic (Chain, Romanche, Vema), and her work directly contributed to the recognition of the role of mid-ocean ridges in plate tectonics and oceanic accretion. Heezen &Tharp physiographic diagram of the North Atlantic, painted by H.C. Berann in 1968 And at Lamont in July 2001, after she received the Lamont- Doherty Heritage Award. Photo credit: Bruce Gilbert Marie Tharp, July 30, 1920 (Ypsilanti, Michigan) in New York just after she was hired in Maurice Ewing’s lab at Lamont –August 23, 2006 (Nyack, New York). Mid-Atlantic Ridge Atlantis Seamount Meteor Seamount 10.1029/2008GC002332 2019 GMRT grid Version 3.7 Ryan, W.B.F. et al., 2009, Global Multi-Resolution Topography synthsis, Geochem. Geophys. Geosyst., 10, Q03014, doi: 1957 Heezen &Tharp physiographic diagram of the Azores region, Atlantic Ocean Tharp and Heezen opted for physiographic diagrams instead of maps to represent their bathymetric compilations. These diagrams look outdated, yet given the scarcity of actual bathymetric soundings Tharp and Heezen had to work with, they are remarkably detailed and probably more evocative than maps would have been. As an illustration we show their 1957 physiographic diagram for the Azores region, and as a comparison, a 3D view over the same region using the most recent global bathymetric mapping document: the 2019 GMRT grid.
    [Show full text]
  • Worksheets on Climate Change: Sea Level Rise
    EDUCATION FOR SUSTAINABLE DEVELOPMENT WORKSHEETS ON CLIMATE CHANGE Sea level rise Consequences for coastal and lowland areas: Bangladesh and the Netherlands Sea level rise – Consequences for coastal and lowland areas: Bangladesh and the Netherlands © Germanwatch 2014 Sea level rise Consequences for coastal and lowland areas: Bangladesh and the Netherlands As a consequence of the anthropogenic greenhouse effect A comparison of the two countries, the Netherlands and the scientific community predicts an increase in average Bangladesh, both of which are potentially very much jeop- global temperature and resulting sea level rise. Heated ardised by sea level rise, clearly illustrates the likely im- water, however, expands only slowly because of the heat pacts for humans and the environment, but also shows transfer from the atmosphere to the sea. For this reason, how different the capacities of individual countries are the sea responds to climate change like a slow-to-react concerning their ability to adapt and to protect them- monster – slow but persistent. In the 20th century the selves from the consequences. Bangladesh, one of the sea level already rose by an average of 12 to 22 cm. The poorest and at the same time most densely populated Intergovernmental Panel on Climate Change (IPCC) con- countries in the world, is also one of the countries which cludes that, as a result of climate change, by 2100 the rise will be most affected by the expected sea level rise. in sea levels could increase worldwide by up to almost 1 metre compared to the mean sea level in the years Flooding has already caused damage up to 100 km inland 1986–2005.
    [Show full text]
  • Marie Tharp: ‘The Valley Will Be Coming up Soon’
    Earthlearningidea – https://www.earthlearningidea.com Marie Tharp: ‘The valley will be coming up soon’. Bruce Heezen: ‘What valley?’ ‘A woman scientist in a man’s world’ – what was it like? The story is told of Bruce Heezen and Marie you used echo sounding profiles in 1953 to Tharp on a ship measuring one of the early echo draw a map of the central Mid-Atlantic Ridge sounding profiles of the Mid-Atlantic Ridge in the valley, which you thought was a rift valley and 1950s. Marie said: ‘The valley will be coming up so supported the idea of ‘continental drift’ (as soon’ and Bruce said: ‘What valley?’ plate tectonic ideas were called then) but Bruce Heezen dismissed this idea as ‘girl talk’. If this story is true, it shows that Marie Tharp was your work, and other work showing that the first person to ‘discover’ an oceanic ridge rift earthquake epicentres also plotted the position valley. However, much of the credit was taken by of the rift valley, eventually persuaded Bruce Bruce Heezen because he was the ‘scientist’ and Heezen to accept the theory of plate tectonics; she was his assistant ‘cartographer’; he was a then he and others published several major man and she was a woman at a time when papers on plate tectonics, but your name did science was dominated by men. not appear on any of them. What could be done then? Use this background to discuss with your friends what Marie and woman scientists like her could do about these problems then. Write a list of what could be done.
    [Show full text]
  • EAPS 54-100 Lecture Hall Naming Contest Phase 1 Consolidated Nominations with Narrative Rationales
    EAPS 54-100 Lecture Hall Naming Contest Phase 1 Consolidated Nominations with Narrative Rationales 1 54-1.5 1.5 degrees C is the ambitious target of the Paris Agreement, limiting global temperature increase. The name both reflects the typical use of numbers for lecture halls at MIT, and serves as a reminder of the magnitude of the climate challenge. It also follows closely upon “54-100” which is what everyone calls that room -- referring to fifty- four-one-point-five would be an easy transition. 1.5 degrees is an ambitious (and some would say impossible) goal, but is a level at which the risks and impacts of climate change would be significantly reduced. Even when (if) 1.5 is in the rear view mirror, the name would also serve as a reminder of the human impact on the planet, the collective goals to mitigate this impact, and the universality of people across the globe working together towards a common ambition. 2 Room 417.07 417.07 ppm is the monthly average CO2 concentration at Mauna Loa, for May 2020. In keeping with MIT’s institutional naming traditions, which honor our collective numeric bent, naming the lecture hall Room 417.07, which is the monthly average CO2 concentration in ppm at Mauna Loa in May 2020 (could be changed to reflect CO2 at time of building or dedication) reflects the specific time and climate we live in, and is a prescient reminder of how we got here, where we’re going, and what we can do about it. 3 Tanya Atwater Tanya Atwater - pioneer in plate tectonics, inspirational woman geophysicist.
    [Show full text]
  • Chapter 2 a History of Marine Science
    OIMS/9 Instructor’s Manual CHAPTER 2 A HISTORY OF MARINE SCIENCE SIX MAIN CONCEPTS The ocean did not prevent the spread of humanity. By the time European explorers set out to “discover” the world, native peoples met them at nearly every landfall. Any coastal culture skilled at raft building or small-boat navigation had economic and nutritional advantages over less skilled competitors. The first global exploratory expeditions were undertaken by Chinese admiral Zheng He beginning in 1405. The three expeditions of Captain James Cook, British Royal Navy, were perhaps the first to apply the principles of scientific investigation to the ocean. The voyage of H.M.S. Challenger (1872 – 1876) was the first extensive expedition dedicated exclusively to research. Modern oceanography is guided by consortia of institutions and governments. MAIN HEADINGS 2.1 UNDERSTANDING THE OCEAN BEGAN WITH VOYAGING FOR TRADE AND EXPLORATION Early Peoples Traveled the Ocean for Economic Reasons Systematic Study of the Ocean Began at the Library of Alexandria Eratosthenes Accurately Calculated the Size and Shape of Earth Seafaring Expanded Human Horizons Viking Raiders Discovered North America The Chinese Undertook Organized Voyages of Discovery 2.2 THE AGE OF EUROPEAN DISCOVERY Prince Henry Launched the European Age of Discovery 2.3 VOYAGING COMBINED WITH SCIENCE TO ADVANCE OCEAN STUDIES Captain James Cook: First Marine Scientist Accurate Determination of Longitude Was the Key to Oceanic Exploration and Mapping 2.4 THE FIRST Scientific Expeditions WERE UNDERTAKEN
    [Show full text]
  • Pressure 4117, Tide 5217, Wave and Tide 5218
    TD 302 OPERATING MANUAL PRESSURE SENSOR 4117/4117R TIDE SENSOR 5217/5217R WAVE & TIDE SENSOR 5217/5217R January 2014 PRESSURE SENSOR 4117/4117R TIDE SENSOR 5217/5217R WAVE AND TIDE SENSOR 5218/5218R Page 2 Aanderaa Data Instruments AS – TD302 1st Edition 30 June 2013 Preliminary 2nd Edition 05 September 2003 New version including general updates in text. Rebranded, Frame Work 3 update, please refer Product change notification AADI Document ID:DA-50009-01, Date: 09 December 2011 (ref Appendix 6 ). 3rd Edition 14 January 2014 New property “Installation Depth” added for Tide sensors, effective version 8.1.1 © Copyright: Aanderaa Data Instruments AS January 2014 - TD 302 Operating Manual for Pressure 4117/4117R Tide 5217/5217R, Wave & Tide 5218/5218R Page 3 Table of Contents Introduction .............................................................................................................................................................. 6 Purpose and scope ................................................................................................................................................ 6 Document overview.............................................................................................................................................. 6 Applicable documents .......................................................................................................................................... 7 Abbreviations .......................................................................................................................................................
    [Show full text]